The present invention relates generally to the field of power conversion devices, and more particularly to on-chip voltage conversion devices.
Voltage conversion circuits enable devices to operate at voltage levels that are suited to the functional and performance requirements of the devices. In particular, on-chip power delivery has become important for high performance devices such as processors, where power consumption is high, and power losses due to package parasitics are significant. Step-down on-chip voltage converters enable board-level DC-DC converters to operate at reduced current levels and higher efficiency, resulting in a reduction of power losses including IR losses and Ldi/dt losses.
Switched-capacitor (SC) circuits provide high efficiency voltage conversion for integer conversion ratios (e.g., 2:1 voltage conversion demonstrated at 90%, L. Chang, et al., VLSI Circuits 2010) and enable high voltage power delivery to the chip on which they reside. However, one of the challenges in voltage regulation using switched-capacitor voltage converters is managing output voltage droop and noise induced by abrupt load current changes. Output voltage droop can be very high (i.e., 50-100 mV) resulting in large voltage overhead margins and significantly degraded system-level power/performance.